It must be observed at this point that the world had meanwhile become really musical--or perhaps less truly musical than music-loving. Nay, more; political events, as formerly church ceremonies, could now be celebrated in music. The famous concerto which Beethoven gave in honour of the Vienna Congress was perhaps the first great occasion on which music lent itself in festal manner to the adornment of public events. It was now no longer a mere incident in a commemorative display, but to a great extent pure music; and the rapid and vigorous education of men to instrumental music by the classical masters was the necessary precedent condition of the attainment of this point. In these matters the clavier played its important part as an intermediary and a teacher; it made the innovations into current coin, scattered them among people in their homes, and accustomed their ears to understand better and better the absolute language of music, as it dealt in wider and wider abstractions. The publishers were more active, the issues more frequent, the popular settings more numerous and artistic. Even the great men themselves take a share in the work. A frequent phenomenon in the music-trade is that composers like Clementi, Dussek, and Pleyel, themselves open publishing houses--and secure the advertisement of their wares, oftener perhaps than was really necessary. International exchange became more active year by year. If we look to London, we see Johann Christian Bach at work, helping to give form to the Sonata; we observe Haydn and Pleyel in vigorous rivalry for the favour of the public; we see the virtuoso Clementi from Italy setting up a clavier-school. In Petersburg meanwhile lives the Englishman, Field, one of the chief nocturne-romancists, and Klengel and Berger, the Germans, all three brought out by Clementi. Next we see there also J. W. Hässler, the ex-hatter, who has left behind such agreeable works that Bülow regarded him as a good intermediary between Mozart and Beethoven. In Paris the opera is the favourite agent of musical pleasure. With Gluck the old quarrel between the Italian and the northern manner is renewed. Chamber-music retreats into the back-ground. Schobert and Eckard, decorative musicians, are hardly known beyond the border; and Adam and Kalkbrenner, who restore the fame of French clavier-technique, leave productive art on one side.